![Grimm Exclusive: Mary Elizabeth Mastrantonio to Appear in Season Finale as [Spoiler]](http://l.yimg.com/os/mit/media/m/base/images/transparent-1093278.png "Grimm Exclusive: Mary Elizabeth Mastrantonio to Appear in Season Finale as [Spoiler]")
Former Law & Order: Criminal Intent captain Mary Elizabeth Mastrantonio has signed on to guest star in the season finale of Grimm, TVLine has learned exclusively.
The actress — a 1987 Oscar nominee for her supporting role in The Color of Money — will play the intriguingly-monikered Woman in Black, the latest obstacle for Nick and Hank.
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Grimm, which has already been renewed by NBC, is set to close out its freshman season on May. 18.
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